The primary objective of this project is to build on prior Phase 1 research to improve product sensitivity properties, to refine and test modifications of the Origami Male Condom 1 (OMC 1), and develop a more consumer-acceptable device exclusively for vaginal-penile intercourse, the Origami Male Condom 3 (OMC 3). Made of custom formulated biocompatible, viral-impermeable silicone, the OMC 3 is intended to: 1. Facilitate a more pleasurable and safer sexual experience for both partners, 2. Increase the sensitivity and acceptability of male condoms among those at risk of HIV/STIs, and 3. Encourage and increase motivation for consistent and correct condom use. Two revised product designs of the OMC 3 prototypes will be injection-molded to conduct pre-clinical testing for structural integrity. Upon completion of pre-clinical structural testing and identification of safe prototypes, we propose to conduct two human volunteer studies: 1. A User Preference (UP) Study, to identify a preferred prototype, comparing measures of improved sensitivity and user preference of two prototypes among 10 couples, and 2. A Couples Acceptability &Performance (CAP) Study to investigate the acceptability, and performance of the "preferred" prototype among 36 couples. PUBLIC HEALTH RELEVANCE: We propose clinical research to develop and refine the OMC 3 for vaginal-penile intercourse in a feasibility study with human volunteers and pre-clinically tested for structural integrity. New features, including telescopic folding for easier donning, longitudinal ribs, lose fitting design, and a clitoral stimulation feature will be introduced to provide improved sensation and increased consumer acceptability and performance for both partners.